SOUTHERN CALIFORNIA SEISMOGRAPHIC NETWORK A Cooperative Project of Caltech and the U.S. Geological Survey June 19, 1997 Weekly Earthquake Report for Southern California ------------------------------------------------ June 12 - 18, 1997 Prepared by: Kate Hutton, Seismological Laboratory (kate@bombay.gps.caltech.edu) Lucy Jones, U. S. Geological Survey California Institute of Technology For further information, please contact the authors, or the Caltech Public Relations Office at 818-395-6327. For daily updates, call our Earthquake Information Hotline: 818-395-6977. -------------------------------- This week's Report covers the time period from midnight Thursday morning, June 12, Universal Time (ie. GMT), to midnight Wednesday night, June 18, Universal Time. In local time, the period of coverage is from 5 p.m., June 11, Pacific Daylight Time, to 5 p.m., June 18, Pacific Daylight Time. We detected 172 earthquakes during the seven-day period covered. These Weekly Reports should not be used for archival purposes. Further data processing often changes the magnitudes slightly and, especially during times of high seismicity, sometimes changes the estimates of total seismicity. For the best earthquake catalog currently available, see: http://scec.gps.caltech.edu/catalog-search.html We have had a very quiet week this week. There was only one quake above M3, a M3.4 near the southern Elsinore Fault, just south of the U.S./Mexico border, very early last Friday morning. We got no inquiries. In addition to this, a M2.8 Northridge aftershock on Saturday morning was felt in the northern San Fernando Valley. This quake had an oblique thrust focal mechanism typical of Northridge aftershocks. Table 1 lists the quakes this week that were M2.0 or larger in the central part of the coverage area. Times are local times; if you want Greenwich Mean Time, add 7 hrs to the Pacific Daylight Time or 8 hrs to the Pacific Standard Time listed. Table 1 ------- Date Time N Lat. W Long. Mag ------------------------------------------------------------- 6/11 11:35 pm 33 13.9 116 4.2 2.0 7 mi. NNE of Ocotillo Wells 6/12 4:02 am 33 43.3 116 44.8 2.0 2 mi. SW of Idyllwild 6/12 5:26 am 32 47.7 117 17.8 2.4 2 mi. WNW of Mission Beach 6/12 8:14 am 33 22.5 116 16.8 2.5 9 mi. NNE of Borrego Springs 6/12 6:09 pm 33 18.7 116 24.8 2.0 4 mi. NNW of Borrego Springs 6/13 3:19 am 35 46.7 117 39.0 2.0 10 mi. N of Ridgecrest 6/13 4:16 am 32 36.3 115 52.0 3.4 11 mi. SE of Ocotillo 6/13 4:24 am 34 10.6 116 25.8 2.1 4 mi. NNE of Yucca Valley 6/13 12:15 pm 33 33.1 118 48.7 2.6 15 mi. ENE of Santa Barbara Is. 6/13 2:34 pm 35 59.0 117 40.4 2.3 15 mi. ESE of Coso Junction 6/13 4:30 pm 35 11.0 119 24.0 2.5 4 mi. NE of Taft 6/14 9:23 am 34 16.3 118 29.0 2.8 1 mi. E of Granada Hills FELT 6/14 3:25 pm 35 59.1 117 40.6 2.2 15 mi. ESE of Coso Junction 6/14 11:03 pm 33 37.4 119 4.5 2.1 10 mi. N of Santa Barbara Is. 6/15 1:41 am 34 6.1 116 23.9 2.0 2 mi. ESE of Yucca Valley 6/15 3:02 pm 34 24.6 116 28.0 2.4 20 mi. N of Yucca Valley 6/16 2:09 am 33 28.6 116 33.6 2.0 8 mi. SE of Anza 6/16 1:47 pm 35 32.5 118 34.2 2.2 8 mi. SW of town of Lake Isabella 6/16 7:48 pm 34 22.4 118 39.1 2.1 5 mi. WSW of Valencia 6/16 9:40 pm 34 23.5 116 27.4 2.4 18 mi. N of Yucca Valley 6/17 4:51 pm 35 38.4 116 19.5 2.0 23 mi. S of Shoshone 6/17 11:22 pm 34 20.5 116 27.7 2.1 15 mi. N of Yucca Valley 6/18 1:18 am 34 40.9 120 28.0 2.2 3 mi. NNW of Lompoc 6/18 11:41 am 33 0.1 116 5.2 2.1 10 mi. SSE of Ocotillo Wells 6/18 12:05 pm 35 38.4 117 30.3 2.5 9 mi. E of Ridgecrest 6/18 2:16 pm 34 13.3 116 51.0 2.0 2 mi. S of Big Bear City -------------------------------------------------------------